diff --git a/test/std/containers/associative/map/map.cons/deduct.fail.cpp b/test/std/containers/associative/map/map.cons/deduct.fail.cpp
index ec59c92..d7402b5 100644
--- a/test/std/containers/associative/map/map.cons/deduct.fail.cpp
+++ b/test/std/containers/associative/map/map.cons/deduct.fail.cpp
@@ -9,6 +9,8 @@
 // <map>
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 // UNSUPPORTED: libcpp-no-deduction-guides
+// XFAIL: clang-6
+//  clang-6 gives different error messages.
 
 // template<class InputIterator,
 //          class Compare = less<iter-value-type<InputIterator>>,
diff --git a/test/std/containers/associative/multimap/multimap.cons/deduct.fail.cpp b/test/std/containers/associative/multimap/multimap.cons/deduct.fail.cpp
index 32b53f6..fa6dd92 100644
--- a/test/std/containers/associative/multimap/multimap.cons/deduct.fail.cpp
+++ b/test/std/containers/associative/multimap/multimap.cons/deduct.fail.cpp
@@ -9,6 +9,8 @@
 // <map>
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 // UNSUPPORTED: libcpp-no-deduction-guides
+// XFAIL: clang-6
+//  clang-6 gives different error messages.
 
 // template<class InputIterator,
 //          class Compare = less<iter-value-type<InputIterator>>,